The present invention relates to a method for the preparation of an alcohol from a hydrocarbon compound as the starting material. More particularly, the invention relates to a method for the preparation of an alcohol by the photochemical direct reaction of a hydrocarbon compound and carbon monoxide in the presence of a transition metal complex compound as a catalyst in which the amount of the aldehyde compound produced as a by-product is greatly decreased.
As is well known, a large scale industrial process has been established for the preparation of an alcohol by the so-called oxo process utilizing the hydroformylation reaction of an olefin with carbon monoxide in the presence of a catalyst. This process, however, is economically not quite advantageous because the olefin compound as the starting material must be produced by the high-temperature pyrolysis of a paraffin compound which is a process of low selectivity consuming a large guantity of energy. Accordingly, it is eagerly desired to develop a process for the preparation of an alcohol directly even from a non-olefin hydrocarbon compound as the starting material without using any olefin compound as an intermediate. In this regard, oxidation of a hydrocarbon compound into an alcohol may be within possibility but this process is industrially not practicable due to the problem of difficulties encountered in the control of the successive oxidation reactions.
The inventors have previously proposed a method for the preparation of an alcohol and an aldehyde by the direct reaction of a hydrocarbon compound with carbon monoxide in the presence of a photocatalyst (see, for example, Japanese Patent Kokai 64-6222 and 64-6224). This prior art method, however, has a problem in the relatively low selectivity for the formation of the desired alcohol compound relative to the aldehyde.